I have a few questions...
Any additional details you can provide will help. Thanks.
Hello, the sitefinity version is 9.1. No changes have been made to the modules or site configuration.
Edwin, do you have the recommended memory requirement for running a Sitefinity website?
Sitefinity recommends 500+ MB of memory to run a Sitefinity website, but if you have more, use it. You can read more about that at this URL...
Also, something I have done in the past is generate my own machineKey in the web.config file. I have seen this used when Sitefinity is deployed in a shared web hosting solution. Below is a great article from code project that will show you how to add this to your web.config.
Let me know if either of these items will help.